共查询到20条相似文献,搜索用时 359 毫秒
1.
本文研究了Au/SrTiO3/Au三明治结构中的双极电阻翻转效应, 观察到高、低阻态的电阻弛豫现象. 低频噪声测量表明高、低阻态的电阻涨落表现出1/f行为. 对比试验表明, 高阻态的低频噪声来源于反向偏置肖特基势垒和氧空位的迁移, 强度较大, 低阻态的噪声则源于类欧姆接触底电极区域的氧空位迁移导致的载流子涨落, 强度较低. 同时, 界面上氧空位浓度的弛豫导致了高、低阻态的弛豫过程.
关键词:
电阻翻转效应
低频噪声
氧空位 相似文献
2.
M. I. Nagy 《Physics of Particles and Nuclei Letters》2011,8(9):1033-1036
A novel type of quantum mechanical correlations, hypothesized in the 1990’s, the (squeezed) back-to-back correlations, was
predicted to appear in heavy ion collisions among particle-antiparticle (eg. π+π−, K
+
K
−, p[`(p)]p\bar p) pairs, if their in-medium masses are different from the vacuum values. Observation of this correlation would provide new
insight in the freeze-out dynamics of the created matter. The latest status of the PHENIX measurement, comprising the first
measurement of this new effect, is presented. 相似文献
3.
We present a calculation of the cold nuclear matter effect on inclusive production of J/ψ in d+A and A+A collisions in the framework of the gluon saturation/CGC approach. Our model is based on the observation that the leading production mechanism involves odd number of inelastic interactions with the nuclei. Our numerical calculations are in good agreement with the experimental data in the case of d+Au collisions. However, in Au+Au collisions the cold nuclear matter effect is not suffcient to describe the data. 相似文献
4.
5.
6.
利用分子动力学模拟了Au原子在Au(111)表面低能沉积的动力学过程.采用嵌入原子方法的原子间相互作用势,通过对沉积层原子结构的分析和薄膜表面粗糙度、层覆盖率的计算,研究了沉积粒子能量对薄膜质量的影响及其机制.结果表明:当入射能量Ein25 eV时,沉积层和基体表层均呈现规则的单晶面心立方(111)表面的排列,沉积原子仅注入到基体最表面两层,随着入射能量的增加,薄膜表面粗糙度降低,薄膜越趋于层状生长,入射能量的增加有利于薄膜的成核和致密化;当Ein 25 eV时,沉积层表面原子结构出现了较为明显的晶界,沉积原子注入到基体表面第三层及以下,随着入射能量的增加,薄膜表面粗糙度增加,沉积层和基体表层原子排列越不规则,载能沉积会降低基体内部的稳定性,导致基体和薄膜内部缺陷的产生,降低薄膜质量.此外,当基体内部某层沉积原子数约等于该层总原子数的一半时,沉积原子将能穿过该层进入到基体内部更深层. 相似文献
7.
8.
基于热电子发射和热电子场发射模式,利用I-V方法研究了Pt/Au/n-InGaN肖特基接触的势垒特性和电流输运机理,结果表明,在不同背景载流子浓度下,Pt/Au/n-InGaN肖特基势垒特性差异明显.研究发现,较低生长温度制备的InGaN中存在的高密度施主态氮空位(VN)缺陷导致背景载流子浓度增高,同时通过热电子发射模式拟合得到高背景载流子浓度的InGaN肖特基势垒高度和理想因子与热电子场发射模式下的结果差别很大,表明VN缺陷诱发了隧穿机理并降低了肖特基势垒高度,相应的隧穿电流显著增大了肖特基势垒总的输运电流,证实热电子发射和缺陷辅助的隧穿机理共同构成了肖特基势垒的电流输运机理.低背景载流子浓度的InGaN肖特基势垒在热电子发射和热电子场发射模式下拟合的结果接近一致,表明热电子发射是其主导的电流输运机理. 相似文献
9.
10.
M. V. Tokarev 《Physics of Atomic Nuclei》2011,74(5):799-804
The production of hadrons in heavy-ion collisions at high-p
T
provides an important information on mechanism of particle formation and constituent energy loss in medium. Such information
is needed for search of a Critical Point and signatures of phase transition. Measurements by the STAR Collaboration of charged
hadron production in Au + Au collisions at √s
NN
= 9.2 GeV over a wide transverse momentum p
T
= 0.2−4 GeV/c and at mid-rapidity range are reported. It allows for a first measurement of the spectra for charged hadrons at high p
T
at this energy. The spectra demonstrate the dependence on centrality which enhances with p
T
. The constituent energy loss and its dependence on transverse momentum of particle, and centrality of collisions are estimated
in the z-scaling approach. 相似文献
11.
12.
在分子动力学研究的基础上建立了载能原子的沉积动力学物理模型,并根据在局域环境下的表面原子扩散模型,通过运动学Monte Carlo方法研究了载能粒子沉积Au/Au(100)薄膜的初期生长过程,探讨了载能粒子沉积对薄膜生长的影响及其随基体温度的变化.通过计算机模拟发现:载能粒子沉积的Au/Au(100)薄膜生长仍然呈现层状生长-三维岛状生长-准二维层状.在薄膜生长初期,载能粒子的作用是促进表面原子的成核,增加基体表面的缺陷;在薄膜的生长阶段,载能粒子通过抑制三维岛的生长速率起着平滑薄膜表面形貌的作用.载能粒
关键词: 相似文献
13.
14.
从实验观察结果出发,提出与传统扩散控制聚集(DLA)模型不同的分形生长模型,用Monte-Carlo方法模拟了具有不同界面结构的a-Ge/Au双层膜在晶化过程的分形行为,得到了和实验结果相符合的分形结构。结果表明:在a-Ge/Au双层膜的退火过程中,由非晶晶化潜热形成的局域温度场在分形过程中起主要作用;密集分枝结构的出现是由粒子扩散的局域性引起的;模拟结果还表明DLA形态的分形结构也可以在粒子扩散距离相对短的条件下获得。
关键词: 相似文献
15.
空气和氧气气氛下p-GaN/Ni/Au合金性质 总被引:2,自引:1,他引:1
研究了p-CaN上的Au/Ni双金属层在空气气氛和氧气气氛下合金对其欧姆接触性质的影响。使用同步辐射高强度X射线衍射观察到明显的NiO衍射峰。随着合金时间的增加,NiO和Au的结晶性均明显变好,NiO的衍射峰强度随合金时间的增加而增强,同时发现Au(111)沿CaN的(0001)面择优形成单晶。测得Ni/Au-p-CaN-Ni/Au串联电阻在合金后明显降低,表明接触性质改善与结晶性的提高有关。同时发现氧气下合金比空气下合金形成NiO更快,相应的串联电阻也更快地下降。 相似文献
16.
采用脉冲激光沉积(PLD)工艺,制备了以Bi4Ti3O12(BIT)为过渡阻挡层的Au/PZT/BIT/p-Si异质结.研究了BIT铁电层对Pb(Zr0.52Ti0.48)O3(PZT)薄膜晶相结构、铁电及介电性能的影响,对Au/PZT/BIT/p-Si异质结的导电机制进行了讨论.氧气氛530℃淀积的PZT为多晶铁电薄膜,与直接淀积在Si基片上相比,加入BIT铁电层后PZT铁
关键词:
铁电薄膜
异质结构
脉冲激光沉积(PLD) 相似文献
17.
研究了Ag的厚度、退火时间、沉积温度对于Ni/Ag/Ti/Au电极的反射率及与p-GaN欧姆接触性能的影响. 利用分光光度计测量反射率, 采用圆形传输线模型计算比接触电阻率. 结果表明: 随着Ag厚度的增加, Ni/Ag/Ti/Au电极的反射率逐渐增大; 在氧气氛围中, 随着退火时间从1 min增至10 min, 300 ℃退火时, 比接触电阻率持续下降, 而对于400-600 ℃退火, 比接触电阻率先减小后增大; 在300和400 ℃氧气中进行1-10 min 的退火后, Ni/Ag/Ti/Au的反射率变化较小, 退火温度高于400 ℃时, 随着退火时间的增加, 反射率急剧下降; 在400 ℃氧气中3 min退火后, 比接触电阻率可以达到3.6×10-3 Ω·cm2. 此外, 适当提高沉积温度可以增加Ni/Ag/Ti/Au的反射率并降低比接触电阻率, 沉积温度为120 ℃条件下的Ni/Ag/Ti/Au电极在450 nm处反射率达到90.1%, 比接触电阻率为6.4×10-3 Ω·cm2. 综合考虑电学和光学性能, 在沉积温度为120 ℃下蒸镀Ni/Ag/Ti/Au (1/200/100/100 nm)并在400 ℃氧气中进行3 min退火可以得到较优化的电极. 利用此电极制作的垂直结构发光二极管在350 mA电流下的工作电压为2.95 V, 输出光功率为387.1 mW, 电光转换效率达到37.5%. 相似文献
18.
Spin resonance transport properties of a single Au atom in S–Au–S junction and Au–Au–Au junction 下载免费PDF全文
The spin transport properties of S–Au–S junction and Au–Au–Au junction between Au nanowires are investigated with density functional theory and the non-equilibrium Green's function. We mainly focus on the spin resonance transport properties of the center Au atom. The breaking of chemical bonds between anchor atoms and center Au atom significantly influences their spin transmission characteristics. We find the 0.8 eV orbital energy shift between anchor S atoms and the center Au atom can well protect the spin state stored in the S–Au–S junction and efficiently extract its spin state to the current by spin resonance mechanism, while the spin interaction of itinerant electrons and the valence electron of the center Au atom in the Au–Au–Au junction can extract the current spin information into the center Au atom. Fermi energy drift and bias-dependent spin filtering properties of the Au–Au–Au junction may transform information between distance, bias,and electron spin. Those unique properties make them potential candidates for a logical nanocircuit. 相似文献
19.
Using the Glauber model, we discuss the number of binary nucleon-nucleon collisions in heavy-ion collisions. Based on the latter, after considering the effect of energy loss of the nucleons in multiple collisions, we derive the pseudorapidity distribution of the multiplicity as a function of the impact parameter in nucleus-nucleus collisions. Using this, we analyze the experimental measurements carried out by the BRAHMS Collaboration in Au+Au collisions at √sNN=200GeV. The results are in good agreement with the experimental observations. 相似文献
20.
《Physica E: Low-dimensional Systems and Nanostructures》2009,41(10):3072-3077
Au–CdTe and Ag/Au–CdTe assembles were firstly investigated through the static interaction between positively charged cysteamine-stabilized CdTe quantum dots (QDs) and negatively charged Au or core/shell Ag/Au nano-particles (NCs). The CdTe QDs synthesized in aqueous solution were capped with cysteamine which endowed them positive charges on the surface. Both Au and Ag/Au NCs were prepared through reducing precursors with gallic acid obtained from the hydrolysis of natural plant poly-phenols and favored negative charges on the surface of NCs. The fluorescence spectra of CdTe QDs exhibited strong quenching with the increase of added Au or Ag/Au NCs. Railey resonance scattering spectra of Au or Ag/Au NCs increased firstly and decreased latter with the concentration of CdTe QDs, accompanied with the solution color changing from red to purple and colorless at last. Experimental results on the effects of gallic acid, chloroauric acid tetrahydrate and other reagents demonstrated the static interaction occurred between QDs and NCs. This finding reveals the possibilities to design and control optical process and electromagnetic coupling in hybrid structures. 相似文献